Ground station for air pickups



Jan. 26, 3945. a Q L MM ER 2,367,607

GROUND STATION FOR AIRPICK-UPS Filed Sept. 25, 1941 2 Sheets-Sheet l INVENTOR ATTORNEY jam. 1, 3%45. 5, C PLUMMER 2,367,607

GROUND STATION FOR AIR PICK-UPS Filed Sept. 23, 1941 2 Sheets-Sheet 2 S ENVENTOR STUART Cl w/Wm BY W1 ATTORNEY Patented Jan. 16, 1945 GROUND STATION FOR AIR PICKUPS Stuart Crosby Plummer, Wilmington, Del., assignor to All American Aviation, Inc., Wilmington, DeL, a corporation of Delaware Application September 23, 1941, Serial No. 411,961

7 Claims.

The invention relates to ground stations for air pick-up systems and more particularly to ground stations utilizing a transfer rope stretched between two poles. According to a preferred form of the invention the ground station comprises a set of poles, each of which is of sectional construction and has a pointed stake to facilitate setting up and taking down the poles. Each pole may conveniently comprise three sections connected together by telescopic couplings. The lower and intermediate sections may be of sturdy construction to give the poles sufficient rigidity to hold the transfer rope in substantially fixed position. The upper sections may be of thin or frangible material, so that if, by accident, the aircraft should engage the poles, they will easily give or break without injuring the aircraft. The lower sections may have the stakes secured in overlapping relationship thereto, exposing their upper ends to facilitate driving into the ground by a hammer or other suitable device. If desired, the lower sections may be provided with rings or other guiding devices in line with the stake so that the intermediate sections may be used as a hammer to drive the stakes into the ground.

A further feature of the invention is the utilization of the signal flags at the top of the poles to support the transfer rope thereb holding the signal flags in the plane of the poles to make them more easily visible to the aircraft which is to pick up the load.

The invention also consists in certain new and original features of construction and combinations of parts hereinafter set forth and claimed.

Although the novel features which are believed to be characteristic of this invention will be particularly pointed out in the claims appended hereto, the invention itself, as to its objects and. advantages, and the manner in which it may be carried out, may be better understood by referring to the following description taken, in connection with the accompanying drawings forming a part thereof, in which Fig. 1 is a diagrammatic representation of a ground station according to the invention, showing an airplane about to pick up the load.

Fig. 2 is a vertical elevation illustrating one manner of driving the poles into the ground.

Fig. 3 is a vertical elevation, partly in section, of a ground pole set up.

' Fig. 4 is a vertical elevation of the frangible top section of the pole showing the flag attached thereto.

Fig. 5 is a fragmentary detail illustrating the construction of the lower section and stake.

Fig. 6 is a section of line 6-6 of Fig. 3, and

Fig. 7 is a section of line 1.-'l of Fig. 2.

Like reference characters denote like parts in the several figures of the drawings.

In the drawings accompanying and forming part of this specification, certain specific disclosure of the invention is made for purposes of explanation, but it will be understood that the details may be modified in various respects without departure from the broad aspect of the invention.

Referring now to the drawings "and more particularly to Fig. 1, the ground station comprises, generally, two poles l0 and H driven into the ground, having flags I! attached thereto, and a ground or transfer rope or loop l2 attached to thefiag by releasing links 44. -The ground rope i2 is in the form of a loop passing through an eye on the load or burden 9 resting on the ground. The load 9 is indicated as a mailing pouch of sufficient capacity to hold considerable mail, but if desired the load may constitute a single pocket for a single message in the event the system is used for example for picking up messages for military purposes.

The aircraft is shown as an airplane I3, having a depending arm or boom l4 suitably secured to the underside of the fuselage, and having a pick-up rope l5 provided with a hook or grapple l6 adapted to engage the ground loop 12 for picking up the load 9. It will be understood that other forms of pick-up mechanism may be used on the aircraft as, for example, a simple line let out of the airplane and having a simple hook or other pick-up device secured to the lower end thereof.

Referring now to the other figures, th ground poles l0 and II are identical so it is only necessary to describe one in detail. Each pole comprises a lower section IS, an intermediate section l9 and a top section 20. The lower and intermediate sections l8 and I9 may be of sturdy construction, sufliciently heavy to impart the necessary rigidity to the poles but sufficiently light for portability. Light metals such as aluminum or other material such as wood, shown for purposes of illustration, answer this requirement satisfactorily. The top section 20 is made of a light frangible material, such as bamboo, which will break or bend readily in case the aircraft should accidentally strike it without injury to the aircraft.

Lower wooden section I 8 has a metal socket or cup 24 suitably pinned or otherwise secured to the reduced lower end thereof. Suitably welded to the socket 24 is an iron stake 2|, having a body 25 of angle iron stock with its lower end tapering to form point 22. The top of the body 25 has an anvil 23 suitably welded thereto and connected by a suitable gusset stay 26 for strength. The stake 2| is secured to the socket 24 in overlapping relation to place the anvil 23 in a convenient position for drivin the stake into the ground by a hammer or other suitable device.

The wooden intermediate section l9 has a reduced lower end 29 and may also have a metal socket 30 suitably pinned thereto for purposes hereinafter described morev in detail. The upper end of lower section I8 is reduced and isprovided with a sleeve 21 suitably pinned thereto, as by pin 28, to receive telescopically the intermediate section. The upper end of the intermediate section I9 is reduced and provided with a metal sleeve-3| suitably pinned thereto, as by pin 34, and the wooden body has asocket of reduced diameter to receive the lower end of the bamboo upper section 20;

The upper section 20 has the flag I! secured thereto. This flag is made of a suitable heavy material, such as canvas, and is of generally triangular configuration suitably'stitched around its periphery and provided with a reinforced band 39 along its upper margin. Grommets 36, 31'and 38 are secured to'the corners of the flag and wire bindings secure grommets 3S and 3'! to the pole 20; engaging the pole with sufficient'tightness to prevent them from slipping down. Secured to the grommet 38 by a thong is'the releasablefastener 42', which comprises a ring 43 having projecting therefrom spring c1ips44, having rounded engaging fingers, andarecess through which the groundloop l2 passes. It will'be understoodthat the fingers of releasable fastener 42 engage with sufficient pressure'to hold the ground'loop |2 in the position shown in Fig. l for pickingup the load; but when the loop" I2 is engaged by the pick-updevice' on the' aircraft, the. rope 2 easily slides between the fingers, freeing'thisrope with out damaging the'poles or flags;

If desired,- arrangement maybe made for driv ing the stakes 2| into the ground'without extra apparatus. To thisend, the'lowerisection I8 is provided with a set ofstraps'4-5 and 46 (see also Fig. '7) suitably secured to the" section l8, and forming guides through which the intermediate section l9 may slidably-pa'ss: The straps and 48 will be bent to fit the hexagonal configuration of the pole sections. section |8-in one hand andmoving the intermediate section l9- up and down, a series of blows may be caused by engagement'of the ironisocket 30 against the anvil 23 of the stake 2|, by which the stake may be driven'into the ground as illustrated in Fig. 2. In some cases, where the ground is-soft,'the stake 2| may be driven'into the ground merely by pressure of the footon the'anvil 23 without requiring the use" of any hammering device.

Thus, a ground station isprovidedwhich is efficient and reliable-and yet of a comparatively inexpensive construction. It is adequately suited for portable use and may easily be carried by an army truck to permit setting up the ground station at different points desired for purposes of strategy. The poles, when'set up; may ris about 20 feet above the-ground and they may be located about 20 feet apart"although,"of course, these dimensions may vary, somewhat depending'upon Thus; by'holding the lower portin'g'the ground wire or loop l2.

conditions. To setup the station, it is only necessary to drive the stakes 2| into the ground, then engage the ground rope I2 with the releasable connections 44 and with the load 9, then place the upper sections 20 in the sockets-35 and the intermediate sections IS in the sockets of sleeves 21. The ground station may just as easily be taken down by reversing the setting-up operation. In some cases, where portability is not desired, the stakes 2| may be dispensed with and permanent sockets (not shown) mounted in the round in which the sockets 24 on the lower sections l8 may be inserted.

The flags I! have the structural duty of sup- The grommets 36 and 38' are located in the reinforcing band 39 and thus the flags are sufficiently strong to perform this duty. This arrangement has also the important advantage of automatically holding the flags H in the plane of the poles l0 and II, transverse to the direction of travel of the aircraft picking up the load. This places the flags in the position of maximum visibility regardless of the direction of the wind. The flags may be of international orange color and the poles may be painted in wide bands of international orange and white as indicated by 32 and 33 in' Fig. 1 to improve visibility. The relatively sturdy construction of the intermediate and lower sections imparts sufficient rigidity to prevent swaying in the wind, and to hold the ground loop 2 in moderately fixed position, while the bendable or frangible nature of the top section's 2flprovides a safety measure, avoiding damage to the aircraft in case it should accidentally hit thetops of the poles.

In addition, the flage are so shaped that the load imparted thereto by the pick-up loop is distributed to the two points by which the flags are attached to the uppersection. Thus while the upper sections are relatively weak they will'n'ot be bent by the weight of the loop. I

While certainnovel features of the invention have been disclosed herein, and are pointed out in the annexed claims, it will be understood" that various omissions, substitutions and changes may be made by those skilled'inthe art without depart ing'from the spirit of the invention.

What is claimed is:

i. In an air-'pick-up system, spaced ground poles having their lower ends afllxed to the ground andhaving flags attached to their upper ends, said flags having one edge thereof attached't'o the poles; another edge having a releasing link, a transfer rope comprising a closed loop passing through'said releasing links and having an upper ply adapted to be engaged by an aircraft pick up device and a-lower ply extending toward" the ground; a load 'attached to said lower ply, said transfer rope holding the plane of saidflags transverse to the direction offiight of the air craft.

2. In an'air pick-up system, spacedground poles' having. their lower ends afiixe'cl tothe" ground and having flags attachedto their upper ends, said flags beingof substantially triangular configuration and having one edge thereof at tached to said po1es,-the opposite corner'having a; releasing link, reinforcing means along'the upper edge of said flags, a transferrope comprisingeclosed loop passing through said releasing links, said rope having an upper plyadaptedto be en gaged byan aircraft pick-up device and a lower' ply extending toward theground, a load attachedto'said lower'ply, said transfer rope holdingvthe plane of said flags transverse to the direction of flight of the aircraft.

3. In an air pick-up system, spaced ground poles having their lower ends afiixed to the ground and having flags attached to their upper ends, a transfer rope connecting said flags and holding the plane of said flags substantially in the plane of said poles.

4. In a portable ground station for air pick-up systems comprising two poles with a transfer line stretched therebetween, each pole comprising a lower and an upper section, said sections having couplings detachable from each other on the adjoining ends thereof to normally hold the sections assembled, a pointed stake having an exposed anvil rigidly secured to the lower end of said lower section in overlapping relation, one of said sections having guide devices attached thereto adapted to receive the other section whereby the upper section may be used as a hammer engaging the anvil to drive the stake into the ground, after which the sections are assembled by their detachable couplings.

5. In a portable ground station for air ick-up systems comprising two poles with a transfer line stretched therebetween, each pole comprising a lower, an intermediate and an upper section, said sections having telescoping couplings detachable from each other on the adjoining ends thereof to normally hold the sections assembled, the lower and intermediate sections being of sturdy construction and the upper section being of considerably weaker material, a pointed stake havin an exposed anvil rigidly secured to the lower end of said lower section in overlapping relation, said lower section having guide rings attached thereto adapted to receive the intermediate section whereby the intermediate section may be used as a hammer engaging the anvil to drive the stake into the ground, after which the sections are assembled by their detachable couplings.

6. In a pick-up station for air pick-up systems, spaced poles, flags attached to the upper ends of said poles at a plurality of points, and a transfer loop releasably attached to and supported by the flags, said flags transmitting stress from the loop to the poles at said plurality of points.

7. In an air pick-up system, a base surface, spaced poles having their lower ends afiixed to said base surface and having flags attached there- 

